Latch structure



April 28, 1931. w, SCOTT 1,802,784

LATCH STRUCTURE Original Filed Oct- 24. 1928 I5 Sheets-Sheet l INVENTOR April 28, 1931. w. A. sco'r'r LATCH STRUCTURE Original Filed Oct. 24, 1928 3 Sheets-Sheet 2 n 7 3 1 u a a w l 1 1 .wn 4

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April 1931- w. A. SCOTT I LATCH STRUCTURE Original Filed Oct. 24, 1928 3 Sheets-Sheet 3 W I INV2TOR Patented Apr. 28, 1931 UNITED STATES SYLVANIA PATENT OFFICE WILLIAM A. SCOTT, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO MCKINNEY MANU- i FACTURING COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENN- LATCH STRUCTURE Application filed October 24, 1928, Serial No. 314,654. Renewed June 4, 1930.

i latch mechanism wherein the latch bolt head is dead-locked when the door is in the closed position.

Another object of my invention is to provide a latch mechanism, wherein the latch bolt head is dead-locked in the latch bolt guide when the door is in the closed position.

Another object of my invention is to provide a dead-locking latch bolt that may be used in conjunction with various types of locks and latches.

Still another object of my invention is to provide a dead-locking latch bolt wherein the latch bolt may be locked independently of the main latch or look unit.

A further object is to provide a latch mechanism having a latch bolt, the head of the latch bolt automatically operating to lock the latch bolt against latch bolt retracting movement except by means normally provided for bolt-retracting movement.

Another object is to provide a latch bolt having self-contained operating means for locking the latch bolt'when the door is in the closed position.

Other objects of my invention willbe apparent from the following detailed description, taken in conjunction with the accompanying drawings illustrating certain present preferred embodiments of the invention, wherein Figure 1 is a plan view, partly in section, of a cylindrical type latch mecha nism having a dead-locking latch bolt; Fig. 2 is aside view, partly in section and partly in elevation, of the mechanism shown in Fig. 1 as viewed from the front side of such figure; Fig. 3 is a plan view of my dead-locking latch bolt; Fig. 4 is a side elevational View of my dead-locking latch bolt, parts being broken away to more clearly show the ole tails of the latch bolt-head; Fig. 5 is an end view, in elevation, of the latch bolt shown in Fig. 4; Figs. (Sand 7 are plan and side elevational views, respectively, showing the latch bolt in dead-locked position; Fig. 8 is a detail side elevation of the locking pin; Fig. 9

is a plan view of a modified form of a latch bolt; Fig. 10 is a side elevationof the modifled form of the latch bolt shown in Fig. 9,

parts being broken away to show the details of construction; Fig. 11 is an end elevation of the latch bolt shown in Fig. 10; Figs. 12 and 13 are plan and side elevational views, respectively, showing the modified latch bolt in deadlocked position, and Figs. 14 and 15 are detail plan and side elevational views, respectively, of the locking pin used in the modified latch bolt.

Referring to Figs. 1 and 2 of the drawings, a door 1, adapted to co-operate with a door jamb 2, to effect a closure, is provided with a suitable latch mechanism, such as the'cylindrical type as illustrated at 3, operable to retract a dead-lock latch bolt 4, by the operation of the inside and outside knobs 5 and 6 provided therefor. I

Other than the latch bolt, the parts thus far enumerated may be of any suitable type or form of latch or lock'as shown for example in the lVreadPatent No. 1,720,636, issued July 9, 1929.

The latch bolt 4 is provided with the usual bevel end, to cam the latch bolt inwardly when engaging a strike plate 9, suitably secured to the door j amb'2, and to maintain the door in the closed position. Thestrike plate 9 may be of any suitable type to co-operate with the latch bolt. I 1

The latch bolt 4 comprises a threaded stem 10, a double bolt head, comprising bolt head 11 and bolt head slide 12, a locking pin 13 and means for operating the locking pin (Figs. '3, 4 and 5). The bolt head slide 12 is slidably dovetailed into the upper side of the bolt head 11 and is provided with a longitudinally-extending groove 14, centrally disposed therein. The groove 14 is adapted to receive and position a spring 15 that rests against the end of the groove, the other end of the spring engaging a lug 16 of a bellcrank lever 17 upwardly projecting therefrom into the groove 14. The lever 17 is pivotally mounted by the pin 19 in a recess 18 in the end of the bolt head 11, substantially beneath the groove 14. The lower side of the lever 17 is bifurcatedto receive the threaded stem 10 and is pivotally connected thereto by the pin 20.

The locking pin 13 is slidably positioned in a vertical bore in the bolt head, passing through the recess 18 to one side of the lever 17 The ends of the locking pin 13 are flush with the top and bottom sides of the bolt head 11 and 12, the upper end of the pin being provided 'witha reduced portion 21, adapted to :be slidably secured in an inclined slotted groove 22, longitudinally extending in the upper side oi the bolt head slide 12. The side of the lever 17 adjacent the locking pin 13 projects outwardly to :operatively engage a recess 23 in the locking pin.

Referring to Fig. 2, the latch bolt is slidably positioned in a latch bolt guide plug 2%, suitably secured in a lateral bore or recess 26 in the free edgeof the door 1. The locking pin 13 is adapted to engage a slot 25, positioned for 'co-engagement therewith, in the plug24, to dead-lockthe latch bolt.

The operation of the dead-lock is as follows:- When closing the door 1, the latch bolt 4 engages the strike plate 9 to cam the latch bolt into the guide plug 24,-in the usual manner. When the door is fully closed, (Figs. -1 and 2) thebolt head 11 is projected into a recess in the strike plate in the usual manner =while the bolt head slide l2'abuttin'g the side of the strike plate remains retracted. A

The bolt head 11 is projected outwardly while the-slide 12 is held stationary by the keeper plate 9 as shownin Fig. 2, and the lever 17 compresses the spring 15 until the locking pin 13 is aligned with the slot 25. When in this position, the spring 15 causes the lever 17 to rotate about the pivot 19, forcing the locking pin downwardly into engagement with the slot'25'in the guide plug'24, thereby locking the latch bolt.

The latch'bolt, when in the locked position, may be retracted onlyby the operation of either knob when the door is not locked. Whenthe door is-locked, the latch bolt is operative by turning the knob irom'the inside, or by the key from the outside.

When retracting the latch bolt, by the operation iofeither knob, the stem 10 moves in.- 'wardly,causing the lever 17 to raise the lock- "ing pin 13. The pin 13 is withdrawn from slot 25,'thereby unlocking the bolt head from the bolt guide. The spring 15 now forces the bolt head 11 inwardly into alignment with the bolt head slide 12, to clear the recess in the strike plate.

Thus it will be noted that I have provided a positive lock forthe latch bolt. The latch bolt is so constructed andoperates in such a manner that it is readily adaptable for use with various types of locks and latches for p'ositivelylocking such closures as desired.

Referring now-to Figs. 9, 10 and 11,1 have showna modified form'of latch bolt. A bolt head 27 is provided with an arcuate bolt head slide 28 pivotally mounted thereon and adjacent to the bevel end of the latch bolt. The bolt head slide 28 is provided with an arcuate groove 29 adapted to receive and position a spring '30.

The spring 30 has engagement with a lug 31, upwardly projecting into the groove 29 from the bolt head 27. The varcuate .edge of the bolt'head 'sli de28 .is partlyrecessedand inclined as at 3a to engage a reduced portion 32 oialocking pin 33. The locking pin'33 is slidably positioned in a vertical bore in the bolt head .27, passing through :a longitudinal recess or bore 35 toward one side thereof. The endsot the locking pin 33 are flush with the-upper and lower sides of the latch bolt,-

ception that the bolt lhea'd slide 28 :rotates upon the bolt head 27 to permit the locking pin 33 to be moved downwardly into :enga'gement with the slot 25'in2the guide plug 24. When in the dead-locked position, thelateh bolt assumes a position as shown in Figs. 1-2 and '13.

The operation and assembly ofi'myiinvention will be apparent from the foregoing description. Various changes and modifications may be made without departingtrom the scope of the appendedclaims.

I claim as my invention 1. A latch structure comprising .a latch bolt having a bolt head, a *bolt head :sliole mounted thereon, a lever pivotally mounted in QEIQOESSQCl portion of theibolt head, 11168.115 yielda'bly connecting said lever'and said bolt head slide, alocking pin operatively connected to said lever and means 'for maintaining the bolt head slide in retracted 'position'to cause the locking pin to assume a locking position. i Q

2. A latch structure comprising a latch bolt having a bolt head, a bolt head slide mounted thereon, means 'yieldabl'y connecting said bolt head andboltl'head-sli-de, a looking pin held in non-lockingposition by said bolt head slide, and means operable to position said locking pin to dead-lock said latch bolt when the'bolthe'ad slide :is in a retracted position.

3. Latchbolt structure comprisinga latch bolt stem, .a latch 'bolt head'divided into two parts, means yieldably connecting said parts, a locking pin guided by the latch bolt head and held in non-locking position by one of said parts, and means operable to position the locking pin in a locking position to deadlock the latch bolt.

4. Latch bolt structure, comprising a latch bolt stem, a bolt head, a bolt head slide, means yieldably connecting said bolt head and bolt head slide, a locking pin guided by the bolt head and held in non-locking position by said bolt'head slide, and means operable to position the locking pin in a position to deadlock the latch bolt.

5. Latch bolt structure comprising a latch bolt stem, a bolt head, a bolt head slide rotatably mounted thereon, means yieldably connecting said bolt head and bolt head slide, a locking pin guided by the bolt head and normally held in a non-locking position by said bolt head slide, and means operable to cause the said pin to assume a locking position to deadlock the latch bolt.

6. Latch bolt structure comprising a latch bolt stem, a bolt head, a bolt head slide rotatably mounted thereon, means yieldably connecting said bolt head and bolt head slide, a locking pin guided by the bolt head and normally held in a non-locking position by said bolt head slide, and means operable to withdraw said pin when in the locking position.

7. Latch bolt structure comprising a latch bolt stem, a bolt head, a bolt head slide rotatably mounted thereon, means yieldably connecting said bolt head and bolt head slide, a locking pin guided by the bolt head and normally held in a non-locking position by said bolt head slide, and means operable to withdraw said pin when in the locking position and to retract said bolt head.

8. The combination with a door of latch structure carried thereby, such structure comprising a bolt member, a dogging member a connected with the bolt member and having a detent normally substantially within the confines of the bolt mechanism and adapted to project therefrom to operative position for dogging the bolt member, and means positioned to be engaged by a striker plate upon closing of the door for rendering the dogging member operative.

9. Bolt mechanism, comprising a reciprocable bolt member, a head connected therewith, a slidable detent associated with the head and movable outwardly thereof to dead-locking position when the head is projected, means for moving the slidable detent out of deadlocking position upon a retractive movement of the reciprocable bolt member, and means normally stationary with respect to the bolt member for controlling movement of the detent, such means being adapted for movement relative to the bolt member to permit movement of the detent to dead-locking position.

10. Bolt mechanism for connection with a door and adapted for cooperation with a door jamb, comprising a bolt member, a guiding device for the bolt member, a dead-locking device for the bolt member effective when in operative position for engaging said guiding device, and means adapted to engage a portion of the door jamb for rendering the deadlocking device operative.

11. The combination with a door of latch structure carried thereby, such structure comprising a latch bolt head, a dogging member carried by said head, and means positioned to be engaged by a strike plate upon closure of the door for placing said dogging member under tension-to actuate the same.

In testimony whereof I, the said WILLIAM A. Soo'r'r, have hereunto set my hand.

WILLIAM A. SCOTT. 

